1. Technical Field
The present disclosure relates to electrosurgical systems and devices for performing medical procedures. The present disclosure relates to the administration of beneficial agents in general, which include any physiologically, pharmacologically active and/or psychotropic substance(s). More particularly, the present disclosure relates to a drug-delivery cannula assembly suitable for use with medical devices, such as for example, electrosurgical devices, and electrosurgical systems including the same.
2. Discussion of Related Art
Surgical techniques and instruments have been developed that allow the surgeon to perform an increasing range of surgical procedures with minimal incisions into the skin and body tissue of the patient. Minimally invasive surgery has become widely accepted in many medical specialties, often replacing traditional open surgery. Minimally invasive surgical procedures where trocar assemblies are desirable or even necessary are continually increasing in number and variety.
Minimally-invasive surgical procedures are performed throughout the body and generally rely on obtaining access to an internal surgical site through a relatively small pathway, often less than one centimeter in diameter, to the surgical site. One method of providing such a pathway is by inserting a cannula and trocar assembly through the skin of the patient. Commonly, to place the trocar-cannula, the penetrating tip of the obturator of the trocar is pushed through the skin and underlying tissue until the distal end of the cannula is within the body cavity. Alternatively, some trocar devices have a blunt obturator for placing the cannula through a previously-made incision. Once the trocar has been properly positioned, the obturator is removed and the cannula is then available as a pathway between the surgical site and the exterior of the patient's body through which the surgeon may introduce the various surgical instruments required to perform the desired procedures. Surgical instruments insertable through a cannula include forceps, clamps, scissors, probes, flexible or rigid scopes, staplers and cutting instruments.
The term “trocar” originally referred to a pointed device for penetrating body tissues having a three-faceted pyramidal point. Commonly, a trocar includes an obturator assembly including a shaft having a proximal end connected to a hand grip and a sharpened, pyramidal or conical tip at the distal end of the shaft for penetrating body tissue. Trocars may have their obturators secured to the hand grip so that the obturator cannot rotate separately from the hand grip. Some obturators include a tip portion that is detachable and disposable.
“Trocar” is a term now widely used to describe surgical instruments for placing an access cannula into a body cavity for endoscopic surgery, including laparoscopy, arthroscopy and thoracoscopy. This type of trocar device includes a trocar cannula, also referred to as a trocar tube or sleeve, with an obturator assembly removeably inserted through the lumen of the cannula for penetrating the body tissue.
Trocar assemblies are typically made of metal to facilitate sterilization and re-use. Medical grade stainless steel and titanium metal are commonly used.
Treatment of certain diseases requires the destruction of malignant tissue growths, e.g., tumors. Electromagnetic radiation can be used to heat and destroy tumor cells. Treatment may involve inserting ablation probes into tissues where cancerous tumors have been identified. Once the probes are positioned, electromagnetic energy is passed through the probes into surrounding tissue.
Electrosurgical devices utilizing electromagnetic radiation have been developed for a variety of uses and applications. A number of devices are available that can be used to provide high bursts of energy for short periods of time to achieve cutting and coagulative effects on various tissues. There are a number of different types of apparatus that can be used to perform ablation procedures. Typically, microwave apparatus for use in ablation procedures include a microwave generator that functions as an energy source, and a microwave surgical instrument (e.g., microwave ablation probe) having an antenna assembly for directing the energy to the target tissue. The microwave generator and surgical instrument are typically operatively coupled by a cable assembly having a plurality of conductors for transmitting microwave energy from the generator to the instrument, and for communicating control, feedback and identification signals between the instrument and the generator.
The benefits provided by controlled delivery of active agents for the treatment of injury or disease are well recognized in the art and various approaches have been taken to realize the goal of delivering active agents at desired rates over predetermined periods of time. Various different implantable controlled delivery formulations are known in the art, and various different mechanisms have been employed for delivering an active agent from implantable formulations at a controlled rate over time.
Medical imaging has become a significant component in the clinical setting and in basic physiology and biology research, e.g., due to enhanced spatial resolution, accuracy and contrast mechanisms that have been made widely available. Medical imaging now incorporates a wide variety of modalities, e.g., computed tomography (CT) and magnetic resonance imaging (MRI), which noninvasively capture the structure and/or function of the human body. Such images are acquired and used in many different ways including medical images for diagnosis, staging and therapeutic management of malignant disease.
Medical image processing, analysis and visualization play an increasingly useful role in disease diagnosis and monitoring as well as, among other things, surgical planning and monitoring of therapeutic procedures. A contrast agent may be used for enhancement of the contrast of structures or fluids within the body (or region of interest) in medical imaging to allow visualization and evaluation of lesions seen minimally, if at all, with imaging alone. There is a continuing need for devices capable of dispensing a contrast agent to enhance the visualization of the lesion during a surgical procedure.
Despite advancements in the use of electrosurgical devices for treating biological tissue, there are still concerns for tumor reoccurrence. A further continuing need exists for devices capable of dispensing a controlled delivery formulation of a desired active agent, which may help reduce or eliminate tumor reoccurrence.